Require extern "Rust" fn main() exactly

src/test/compile-fail/bad-main.rs

@@ -8,6 +8,4 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// error-pattern:expected `fn()
-
-fn main(x: int) { }
+fn main(x: int) { } //~ ERROR: main function expects type

src/test/compile-fail/extern-main-fn.rs

@@ -0,0 +1,11 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+extern fn main() {} //~ ERROR: main function expects type

src/test/compile-fail/main-wrong-type-2.rs

@@ -9,5 +9,5 @@
 // except according to those terms.
 
 fn main() -> char {
-//~^ ERROR Wrong type in main function: found `extern "Rust" fn() -> char`
+//~^ ERROR: main function expects type
 }

src/test/compile-fail/main-wrong-type.rs

@@ -14,5 +14,5 @@ struct S {
 }
 
 fn main(foo: S) {
-//~^ ERROR Wrong type in main function: found `extern "Rust" fn(S)`
+//~^ ERROR: main function expects type
 }